Field
The present disclosure is directed to phosphorous containing glass having antimicrobial efficacy and methods of making such glass. In particular, the disclosure is directed to a transparent, chemically strengthened glass with antimicrobial properties that may have a functional coating on the glass that does not interfere with the antimicrobial efficacy of the glass.
Technical Background
Recently, the use both metallic silver particles and silver salts have been described in the patent and technical literature as a means for imparting antibacterial properties to a variety of materials. Silver ions interact with a wide range of molecular processes within microorganisms resulting in a range of effects from inhibition of growth and loss of infectivity to cell death (cytotoxicity). The mechanism depends on both the concentration of silver ions that are present and the sensitivity of the microbial species to the silver ions. Contact time, temperature, pH and the presence of free water all impact both the rate and extent of antimicrobial activity.
The prevalence of “touch screens” in contemporary society gives rise to many surfaces that can harbor microbes, bacteria and viruses, and these microbes can be transferred from person to person. Antimicrobial activity at high relative humidity and physiological temperatures (e.g., about 37° C.) is achievable. However, at ambient conditions (e.g., about 42% relative humidity and about 23° C.) the efficacy of silver ions decreases. Accordingly, a need exists for a glass that has improved efficacy of silver ions at ambient conditions.